Power transmission



April 12, 1960 c, MAY 2,932,217

POWER TRANSMISSION 2 Sheets-Sheet 1 Filed June 7, 1956 INVENTOR.

Claude Hector May April 12, 1960 c. H. MAY 2,932,217

POWER TRANSMISSION Filed June 7, 1956 2 Sheets-Sheet 2 FIG. 5

ABCDEFGH l I I E I i 8 INVENTOR.

Claude Hector May BY 3 a n; om

2,932,217 POWER TRANSMISSION Claude Hector May, Columbus, Ohio 7 Application June 7, 1956, Serial No.5s9,9'09 9 Claims. (Cl. 14-410) This invention relates to power transmission and, more particularly, to pulley construction and flange arrangements in belt or flexible coupling drive power transmission aparatus. This invention is particularly useful in variable speed V-belt transmissions'having'a plurality of belts.

As described in patent application Serial No. 216,183, filed March 17, 1951, now Patent 2,754,691 of which this is a continuation-in-part, in multiple belt power transmission it is very important to control the tension in the plurality of belts so that the belts are equally loaded and tension is substantially the same in each belt.

, In adidtion, it is important in belt drives maintain 'borreCt belt alignment at all speeds in all power trans- -rhission ratios. This is particularly critical in closely 'oupled belt drives having a relatively short distance between centers of the driving and driven shafts.

Briefly, this invention comprises an arrangement of pulley-flange couplings and interconnections in conjunction with driving and drivenshafts wherein the flanges, with the exception of two flanges in all pulley groups, are free to move axially, and to position themselves so that each of the several belts in the drive operate at substantially equal tension and loading. i

In the past when two or more-belts have been used to drive one device from one source, it has been customary to use very close tolerances on the pulley-groove dimensions and to use matched belts. Even with such extreme care, however, the mechanical effici'ency of a multiple belt drive has been invariably lower than'that of a single beltdrive, because of remaining inaccuracies in manufacture of the component parts. Thisinvention whereby more than one belt may 'be used to drive a device, and the arrangement of the comprises an apparatus sliding flared fianges is such that there is complete balance of loads between the belts. While in some multiple belt, power transmission installations the belts are only lightly loaded withrespect to their design capacity, and therefore alignment of the several belts and variation in tension among the several belts does not cause undue difficulty, suchinstallations are inefiicient fronran original cost and'excess drive friction standpoint.

belts are heavily load d t-or near the design capacity of the belts, factors such as belt alignment, equal tensions and loading between the several, belts of the belt drive become veryimportant.

It is thus an objectof i v I multiple-V-belt power transmission apparatus wherein the loads transmited by the belts are equally distributed and are self-distributing. It is a further objecttoprovide a multibelt power transmission apparatus which is self- It is an object of this invention to provide a multibelt power transmission apparatus adapted "to be shifted and this invention to provide ,a

In installations in which the adjusting 1n accordance w th the variations in commenvaried with respect to speed and power ratios without variation in belt alignment. It is another object to provide multibelt power transmission aparatus speed and power transmission ratio may be conveniently varied by changing the distance between flared flanges of the pulleys of the apparatus without changing thealigriment of the several belts, and at the same time maintaining the balance of tension and load existing between the several belts of the apparatus. I

Another purpose of this invention is to provide multibole-power transmission aparatus having a differential drive etiect between 'each of a plurality'of power outpiit sources. It is a purpose to provide this diflerenti'al'efifeet in'a construction that provides proportionaltorque to output sources that rotate at different speeds. a

"Io-these and other ends, this invention comprises apparatus, a preferred form of which" is disclosed in the following description and attached drawings.

In the drawings: v Fig. '1 is an elevation view, partially schematic, illustr'at'ing the transmission of power in a multibelt arrangemnt'according to this invention;

Fig. 2 isa longitudinal section view taken along the line 2--2 of Fig, 1, showing pulleys on 'a driving shaft and pulleys on a driven shaft, connected by two V belts according to this invention; I, Fig; 3' is a'sectional view taken on the line Fig. '2 i g Fig. 4 is a sectional view taken on the line of Fig. 2; Fig. 5 is a longitudinal sectional view showing a multibelt arrangement of a plurality of pulleys operated'by different means; i 'Fig. 6 is a sectional view taken on the line 6-6 of H25 5;

Fig. 7 is rangement of a multibelt greater than two and V i i v Fig. 8 is a plan or elevational view showing a sches -s or an elevational view showing a schematic ar drive having a number of pulleys 'rnatic arrangement of a multibelt drive wherein separate,

driven units are provided with power from a single dritting unit. I Referring to Fig. 1, multibelt power transmission ap; paratus, designated generally as' 20, comprises driving pulleys 21*21 associated with driving shaft 18; driven pulleys Zn- 23 associated with driven shaft 24; and belts The designation of shaft 18 and pulleys 21 -2 1 as driving and the shaft 24 and pulleys 23- 23 as driven" is established as a matter of descriptive convenience only. It should be recognized that in a drive of this type, either shaft may be the driving shaft and either shaft may be the driven shaft, and'thus the functions are reversible. Referring to Figs. 2 and 3 with particularity, a double pulley is shown wherein flared or coned flange '39 fixedly attached to" shaft 18 by means of welded o1 blazed joint 224. Shaft '18 is hollow and positioned therein is piston 215. O-ring 217 .is provided as a seal, anda fluid such as oil is brought in through pipe 200 into chamber 202 enclosed by flange cap 201, which is threaded on to the shaft 18 by means of threads218. Sp ng for chamber 202 is provided by packing 203 and suit lfe seal or .O ring 204. I I I Connected to piston 215, by means of pins 22%222, is sliding flared flange 42 connected to splines 220%220 by means of welded or brazed joints221 2 21. Splines EMF-$20 are adapted to slide in slots 223-2 23"and fsiniilar slots '225;22S. Adapted to slide in thesam'e slots2 232 23' and in the similar slots 225- -225"a fe s plines23 lY-*230, at each end of which there are securely fastened by means of welded or brazed. joints 231%2'3'1 flared flanges 2'32 and 233. Positioned between res ec- "ivenairges 42 and 232 and between flanges 233 "and 39 are belts 2M2.

in which he During rotation of pulleys 21-21 an increase in fluid pressurewithin shaft 18 causes piston 215v to move to .the shaft 18, it will assume, upon such movement of flange 42, such a position between that flange and the fixed flange 39 as will correspond to equaltensions in the two belts 22--22.

Movement of the belts 22-22 outward toward the periphery of the pulley flanges increases the linear speed of the belts increasing the speed ratio of the drive. On

the other, hand, if during rotation of pulleys 21-21 the fluid pressure within shaft 18 is decreased, the tension in the belts will cause the belts to move toward the axis .of the pulleys 21-21 and the space between pulley flanges 42 and 232 and between flanges 233 and 39 will be increased. Movement of the belts 2 2-22 toward the axis ,of the pulleys causes the linear speed of the belts to de crease and the speed ratio to decrease also.

The net results of the flange arrangement above described is to enable both belts 22-22 always to run at both transmit equal amounts of power and therefore both must be at the same power ratio. It does not, in fact, matter if the two belts are not equal in length or width, they still run at the same ratio and transmit the power .equally. It will be seen that should one belt not be transmitting one-half of the power, but some lesser amount, then its tension would be less than the other belt. This lower tension would immediately result in a lower thrust on the corresponding sliding flange pair 232, 233. However,. since the flange pair 232, 233 is free to slide axially, it would be impossible to maintain this unbalanced equilibrium and the flange pair would move toward the belt having the lower tension to equalize the V tension in the two belts. Therefore, unless the two belts are exactly matched, they will not of necessity ride at the same radius in their respective pulleys. Thissystem eliminates the loss of efliciency resulting from the action of pairs of belts in conventional arrangements.

It is apparent that more than two belts could be used in -a multibelt power transmission having pulleys on one shaft arranged in the manner of pulleys 21-21. In such an arrangement similar intermediate flange units such as the subassembly comprising flanges 232, 233, and splines I 230-230 would be interposed between the fixed flange 39 and the movable flange 4'2. Such additional intermediate flange units would in a similar manner be adapted to move axially under pressure of the belts between belts resting on the convergent conical flanges. Such adjustingmovement between the various flanges would provide for balanced uniform tensions and loading in the various belts.

In some applications, it is believed that onlyone flange of each opposed-conical-pulley set need be rotatably fixed relative to shaft 18. Thus, while the splines 230-230 are shown as interposed in grooves, such rotation preverition as provided by the grooves and splines 230 would i not be necessary in some applications as the friction of the belts against one rotatably fixed flange in each pulley would be sufficient to drive and transmit power. r Referring to the driven pulleys 23-23 on which the belts 22-22 rotate, it will be seen that the shaft 24 is similar to shaft 18, in that it is provided with a fluid inlet pipe 123. A bearing 161 is provided to facilitate the rotation of shaft 24 about the fluid pipe 123." Slidably positioned insidehollow shaft 24 is a piston 162, equipped with pins 167-167, which engage flared flange the same tension. While running at the same tension they transmission, when the flanges of the driving pulleys .21-21areurged closer together to increase the speed ratio of the drive, the flanges of the driven pulleys 23-23 v 26. Piston 162 is provided and an increase in fluid pressure in pipe 123 causes move- .and reading from the D; flange B is the one receiving thrust from the piston between opposed coacting 21-21. Since flange 39 4 with scaling 0 rings 164, 165,

ment of piston 162. in a left-hand direction. This movement occurs by reason of the admission of fluid through pipe 123 into the chamber behind and to the right of the piston 162. The piston 162 slides on the pipe 123 and within the cylinder of shaft 24. Pin 167 slides in slot 168. Flared flange 36 is fixedly secured to shaft 24 by means of a resistance-welded joint or brazed joint 160. However, there'are also provided slots 192-192 in each of which 'slidesgone of splinesl93-193. Fixedly attached to splines 193 by welded or brazed joints 194-194 is flared pulley flange 196 and at the other end of splines 193, and fixedly secured thereto by welded or brazed joints 197-197, is flared flange 198. Positioned between these flanges are belts 22-22.

During the rotation of pulleys 23-23, an increase in fluid pressure in line 123 causes piston 162 to move ina left-hand direction. Movement of piston 162 in a leftwill be allowed to move farther apart by means of a decrease in the fluid pressure against piston 162 of the driven pulleys 23. When the fluid pressure against the piston 162 is decreased simultaneously with the increase in fluid pressure against piston 215 in shaft 18, the tension in the belts 22-22 will cause the distance between flanges 196 and 26 and between flanges 36 and 198 to be increased, allowing the belts 22-22 to move inward toward the axis of the pulley 23.

It will be apparent that the same method of load balancing as described in the two-belt arrangement for driven pulleys 23-23 may be employed with three or more belts. 4

Considering th'e' two-belt arrangement of Figs. 2 and left, flange A is coupled to flange within'the shaft; and flange C is the fixed flange. Then in a'three-belt arrangement made with a threepulley group as imagined from a modification of driven pulleys 23-23 in Figs. 2 and 4, the same lettering holds true. The second from the left B is always the thrust flange, and the second from the right E is always the fixed flange. A would always be coupled to D, and C to F, etc. (See Fig. 7.) In a four-belt arrangement the same coupling as above would be used, i.e., second from the left B taking the thrust, second from the right G fixed, A coupled to D, C coupled to F, and E coupled to H. Such an arrangement is shown diagrammatically in Fig. 7.

Referring again to Fig. 2, it is a particularly important feature of thecombination of driving pulleys 21-21 disclosed, and driven pulleys 23-23 disclosed, that as'the movable flangesshift axially and readjust to equal belt tension with changes in speed ratio, the alignment of belts 22-22 remains substantially the same. Thus, during a shiftto a lower speed ratio, the belts 22-22 will move in closer to the axis of shaft 18, as the distance belt flanges increases in pulleys is fixed and flanges 233, 232 and 42 will move to the left, the center line of belts 22 will move to the left also. The center line of the righthand belt 22 will move to the left one-half'of the inflange actuator means vio'usly disclosed Figs. 2, 3, and 4. 6,'appa ratus is disclosed wherein flared pulley asses-e assets distance smas es flanges 39' an 5's, rife eentei' line of the left-hand belt22 will move tothe left a distance equal tothe full increase in width between flanges 39 and 233, and between flanges 232 and 42. In such a change to a low speed ratio as presently under consideration, it is necessary that the flanges 196, 26,36, and 198 of pulleys 23-23 become closer together, accompanied by a shift to the left of belts 22-22. This shift to the left should be equal to the movement of the center lines of the belts 22-22 produced in pulleys 21-21. The arrangement of sliding, fixed, and thrust 'ge connections as herein disclosed for pulleys 23-23 revues this equal belt center-line shift at both ends of the drive combination. t

It will be seen that since flange 36 is the fixed flange among pulleys 23-23, an increase in fluid pressure in pipe 123 will force flange 26 to move to the left causing the left-hand, belt 22 to travel outward between the flanges 26 and 196 toward theperi he y thereof. The outward trjav'el between flanges 26 and 96 moves the center line left-hand belt 22 to the left with respect to flange 196. The, movement of flange 196 to the left also moves flange 198 to the left causing the right-hand belt 22 to y overt; the left accompanied by travel outward toward the periphery of the flanges. v

Accordingly, by reason of the above-described m'oventof flanges'26, 1 96, and 198 the center line of the rights-hand belt 22 Will move to the left One-half ofthe decrease in distance betweenflang es 36 and 198. This move then matches the movemen or the same belt 22 on the pulley 21 over which the belt 22 travels, In a like in nhe'r, the center line of the left-hand belt 22 will'move the left a distance equal to the full decrease inwidth between flanges 196 and 26, and between flanges 36 and 198. This move matches the movement of the same belt :22 on the pulley 21 over which the belt 22 travels.

a It will be apparent that, within tolerances of belt and 1pulley manufacturing, the several belts 22-22 of power transmission apparatus disclosed will maintain substanttially constant alignment through all speed and power s The constant alignment feature of this invention as provided by the driving pulleys21-21 in combination 6 a vided a thrust bearing 158. Flange 39a is fixedly cured to shaft 18a by means of aresistance-welded joint 180. Instead of a resistance-welded joint 180, a brazed joint may be used or any other satisfactory means for attaching flange 39a toshaft 18a. The sliding flange 42a, abutting thrust bearing 158, is attached by means of resistance-welded joints 181-181, or brazing, to a plurality of splines 183-183, which slide in slots 184-184 on p shaft 18a. As shown in Fig. 6, there are six of these slots and splines. Slots 184-184 extend to flange 39a. Also slidably positioned in these slots are splines 186-";- 1 86. .As shown in Fig. 6, there are six splines, which is preferred, but other numbers could be used. Secured to opposite ends of these splines 186-186 byresistancewelded joints 187 -187 are opposed pulley flanges 18 9 and 190. One of belts 22a-22a is positioned between flange 42a and flange 189 and one of belts 22a-22a is positioned between flange 39a and flange 190. Q

In operation, movement of the nut 47 to the right cause movement of flange42a in the same direction. This will cause belt 22a, positioned between flanges 42a and 189, to move toward the outer periphery of the flanges.

However, since the same belt tension will exist in either of belts 22a-22a and since flanges 189 and 190 are connected together by means of splines 186-186 will also cause movement of flanges 189 and 190 toward the right with consequent movement of the other of belts 22a-22a positioned between flanges 190 and39a toward with the driven pulleys 23-2 3 is very important. It

to be recognized that a group of pulleys having the construction of pulleys 21 -21 might possibly be used an both the driving and the driven shaft. But in such arrangement, since the distance between the flanges on the one shaft is increasing and the distance between the flanges on the other shaft is decreasing during "any speed change, the alignment of the center line of the belts :with respect to the axes of the shafts would constantly change. In a like manner the alignment of the belts drive in which both shafts were provided with pulleys constructed in the manner of pulleys 23-23. In apower transmission in which the power transmitted is near maxithe design capacity of the belts, misalignment of 'lielts causes "drastically shortened belt life. This is pro- '-duced 'by uneven and increased belt wear on the sides of the belt; When the center distance betweenshafts is "short a'nd'the drive is thus close-coupled, misaligninnt angles are more aciiteand belt wearis increased critically. In the drive of this invention alignment is maintained irrespective of. the shaft center distance.

In some circumstances it may be desirable to use other than the fluid meanspre- Referring to Figs.

its-ga are arranged and coupled in a manner similar to 27 provided with a raised end 48. There is also prothe outer periphery of that pulley The movement of flanges 189 and .190 will cease upon positioning of belts ,22a-22a such that they are subjected to the same tension. Movement of nut 47 in an opposite or lefthand direction relative to the jack screw 45 permits a corresponding movement of flanges 420, 189, and 190 in a left-hand direction.

, Although the described arrangement of flanges and their coupling has been disclosed with particularityin amultibelt power transmission apparatus that is capable of variablespeed ratios, the arrangement could be used in fixed ratio belt drives in order to obtain the benefit of the higher mechanical efliciency and the freedom from restrictions andv cost of matched pulley flanges and matched belts. In such cases the flanges hitherto indicated as thrust flanges would be other fixed flanges or would be adjustable only to provide for desired belt tension. Otherwise, the flanges wouldbe coupled and free to shift as previously described. 1

Additional advantageous features of this invention are to be found in the particular power transmission arrangement shown schematically in Figs 8. In this embodiyme'nt,.a driving shaft 318 driven by a suitable power source, not shown, rotatively supports a plurality of pulleys 321. The group of pulleys 321 comprises a fixed .fla'nge 339-339 at each of the opposite ends of the group, each having a front or conical face thereof turned in- "ward or toward the center of the group. The flanges 339 are "fixed to the shaft 318 by suitable means, represent'ed schematically by the symbol X in Fig. 8. Central- 1y disposed in back to-back relation is a pair of flared thrust flanges 342-342 adapted to be urged outward by equal forces as represented bythe arrowheadsat the base of flanges 342-342. The equal forces may be provided by conventional means, such asstructural interconnection between the flanges, in a constant speed transmission, or cylinders mechanically connected to each flange actuated by external fluid means at constant equal pressure from the same line, in a variable speed transmission. 'Apair of 'fixedly interspaced back-to-back flared flanges 332 and .333 is axially slidably, disposed on the shaft 318 between each pair comprising fixed flange 339 and thrustflange 342.

A pair of .V belts 322-322 is provided between each e -321w? Ba dve stas s 323-323. Each pair of driven pulleys 323-323 and 321, and the left-hand group is rotatably supported on a separate drivenshaft 324 which is. connected to a separate load, not shown.

" The right-hand pair of pulleys 323-323, as seen in Fig; 8, is constructed similar to the left-hand pair of pulleys 323-323 but in object-to-mirror position. It will be seen that the following description relating to either pair of pulleys 323-323 applies with equal effect 'to the other pair 323-323, but with object-to-mirror visioned as similar to that shown in Fig. 2. In Fig. 8

the arrowheads at the bases of the flanges 326 symbolically indicate the direction of the forces urging the flanges 326 away from the flanges 336.

In each group of pulleys 323-323 is a pair of opposite- 13' disposed flanges 396 and 398, which are fixedly inter- 'spaced with respect to eachother but adapted to slide axially on the shaft 324, line 393.

as symbolically shown by the Before describing the operation of the embodiment shown in Fig. 8, consideration will be given to the nature and function of the forces urging the flanges 342 and 326 :as represented by the arrowheads.

' AS' ifl the previously described embodiments, changes in the amount of the forces of the thrust flanges 342 and 326 will affect the distance between the flanges which make up an individual pulley in any group, and thus, will change the speed and power ratio of the transmission unit. For any given load an increase in the force in the direction of the arrowheads on flanges 342 and a cone sponding decrease in the force represented by the arrowheads on flanges 326 will produce an increase in the speed ratio of the drive unit. Converse changes in the forces will produce an opposite effect on the speed ratio of the drive. During any change in speed ratio, it will be apparent that in the embodiment of Fig. 8, as in previously described embodiments, the belts 322 will maintain substantially constant alignment and that the belts will be substantially parallel in all speed ratios. In addition, it will be apparent that the same transfer of forces from a belt 322 .to another belt. 322 and from a flange 342 to a'flange 333 to a flange 339, and from a flange .326 to a flange 396 to a flange 398 to flange 336 will take place so that the belts 322-322 will operate under substantially equal tensions and will balance the loads between belts. Thus, all of the advantages of the previously described embodiments are to be found in the embodiment of Fig. 8.

During periods of operation when the forces urging the flanges 342 and. ,326 remainconstant and thepower transmission is operating at a constantspeed ratio, the .distance between the flanges of the pulleys 321-321 remains constant. Under such conditions of constant speed operation the flanges 342 are fixedly interspaced and slidable as a unit on the shaft 318.

An additional feature to be found in the operation of .the embodiment of the invention shown in Fig. 8 .is the attainment of a differential effect between the shafts 324-324. If during the operation of the power transmission the torque requirements of the shafts 324-324 become different, the various axially slidable flanges 332,

333,396, and 398 move axially on the shafts 318 and 324-324 to positions which readjust the torque output of each of shafts 324-324. This readjustment varies the speed ratio between the right-hand group of pulleys 323 of pulleys 323 and 321 to accomplish this result.

In many installations, such as on the rear drivewheels 'of'automobiles, adilferential drive effect is necessary between each of the driven units when coupled to a single drive source. This invention is particularly advantageouswhen applied in the power transmission of an automobile or other vehicle, in that it provides proportional torque to the rear driving wheels, one rear wheel being driven by each of shafts 324-324. Asingle driving source, such as an internal combustion engine, may be connected to shaft 318. I f

. When this unit is installed in an automobile, normally both driving wheels will run 'at'the same speed and carry the same torque. However,- on turning a corner, the outsidewheel will run faster than the other. The action of tending to run faster reduces the torque of this wheel, reduces the power pull in the load side of the V belts and also reduces the sliding pulley flange thrust of the driver pulleys to this wheel. At the same time, the opposite is taking place with the inside driving wheel which tends to slow down. The net result of these effects is that two sliding flanges on one side of the driver shaft become unbalanced, with respect to those on the other side, in the matter of axial thrust. The flanges against the belts to the slower wheel are exerting greater axial thrust than the opposite flanges. Since the two sliding thrust flanges which are spaced by the fluidor screw jack between them are free to float on the shaft, the entire assembly of flanges moves axially until, once again, the forces are in equilibrium. At this stage the gear ratios to the two driving wheels are difierent in the exact proportions of the rotative speeds of the wheel, and'the perfect diife'rential effect is achieved.

This power transmission overcomes a disadvantage in many presently used differential gear arrangements. In most conventional units employing a planetary gear system, if the resistance to rotation of either driving wheel is reduced to zero, the opposite wheel receives no torque and fails to rotate. In such a situation, the vehicle'cannot be driven as the one wheel spins and other wheel stands still. In the present invention, should the one wheel lose traction, the differential effect and the shift of the pulley flanges would operate to produce maximum torque on the opposite wheel atthe lowest obtainable speed ratio in the particular design, which in most cases will be adequate to move the vehicle.

Another significant use of this invention is to be found in its application to vehicles having multiple drive, such as four-wheel-drive olf the road vehicles. A separate powertransmission, such as that shown in Fig. 8, would be operatively' connected to the front wheels, and a separate similar power transmission would be operatively connected to the rear wheels, with suitable fluid connections between the fluid chambers in the several driving and driven pulleys of the transmissions; Such an arrangement would provide torque distribution to each vehicle wheel in proportion to the requirements at that wheel.

It will be understood, of course, that, while the forms of the invention herein shown and described constitute preferred embodiments of the invention, it is not intended herein to illustrate all of. the possible equivalent forms or ramifications of the invention. It will also be understood that the Words used are words of description rather than of limitation, and that various changes, such as changes in shape, relative size, and arrangement of parts, may be substituted without departing from the spirit or scope of the invention herein disclosed.

What is claimed is:

1. 'In a multibelt power transmission apparatus, including a driving shaft and a driven shaft, a plurality of pulleys on each of said shafts, said pulleys on one of said shafts comprising a coaxial group of flared flanges including: a flange fixed to said one shaft; a thrust flange oppositely disposed to said fixed flange, rotationally fixed with respect to said one shaft, but axially slidable thereon, and adapted to be urged away from said fixed flange by an external means; at least one pair of fixedly interspaced oppositely disposed flanges free to slide axially senate 9 on said one shaft, said fixed flange being the" second flange from one" end of said group of flanges, and said thrust flange being the second flange from the other end of said group of flanges; and an edge-active belt connecting each pulley on said oneshaft with another pulley on said othershaft. I

2. A multibelt power transmission apparatus according toclairn 1 wherein said at least one pair of fixedly interspaced oppositely disposed flanges are rotationally fixed with respect to said one shaft although free to slide axially thereon;

3. In a multiple V-belt power transmission apparatus including a driving shaft and a driven shaft, a plurality of pulleys having oppositely disposed coaxial conical flanges on each of said shafts, and an edge-active belt connecting each pulley on one of said shafts with a pulley on the other of said shafts, said pulleys on one of said shafts comprising: a flange fixed to said shaft with the conical face thereof outwardly disposed relative to the center of said pulley group; a thrust flange having its conical face oppositely disposed to said fixed flange, rotationally fixed with relation to said one shaft but axially slidable thereon, and adapted to be urged away from said fixed flange by an external means; and at least one pair of fixedly interspaced flanges having their conical faces oppositely disposed, free to slide axially on said driven shaft, one flange of said at least one pair being opposite said fixed flange.

4. A multiple V-belt power transmission apparatus according to claim 3 wherein said at least one pair of fixedly interspaced oppositely disposed conical flanges are rotationally fixed with respect to said one shaft although free to slide axially thereon.

5. A multibelt power transmission apparatus including a driving shaft, a driven shaft, and a coaxial group of pulleys on each of said shafts, wherein said group of pulleys on one of said shafts comprises: a first flared flange fixed to said one shaft; a second flared thrust flange oppositely disposed to said first flange, rotationally fixed with respect to said one shaft, but axially slidable with respect thereto, and adapted to be urged toward said first flange by external means; at least one pair of fixedly interspaced oppositely disposed flared flanges, free to slide axially on said one shaft and positioned between said first and second flanges; and wherein said group of pulleys on the other of said shafts comprises: a third flared flange fixed to said other shaft; a fourth flared thrust flange oppositely disposed to said third fixed flange, rotationally fixed with respect to said other shaft but axially slidable with respect thereto, and adapted to be urged away from said third fixed flange by an external means; at least one pair of fixedly interspaced oppositely disposed flared flanges, free to slide axially on said other shaft; said third fixed flange being the second flange from one end of said group of pulleys on said other shaft, and said fourth thrust flange being the second flange from the other end of said group of pulleys; and an edge-active belt connecting each pulley on said one shaft with a pulley on the other of said shafts.

;6. A multiple V-belt power transmission apparatus including a driving shaft, a driven shaft, and a plurality of pulleys on each of said shafts having a plurality of oppositely disposed coaxial conical flanges, wherein a I group of said pulleys on one of said shafts comprises: a

conical faced first flange fixed to said shaft; a conical faced second thrust flange disposed with the conical sur face thereof opposite to the conical surface of said first flange, rotationally fixed with respect to said one shaft but axially slidable thereon and adapted to be urged toward said first flange by external means; at least one pair of fixedly interspaced conical faced flanges positioned between said first and second flanges having the conical surfaces thereof oppositely disposed, free to slide axially on said one shaft, and wherein a group of'pulleys the: enter at said nags comprises: conical} faced r d ange fixedito said other shaft; a cdnieal faced trust fla ge having" its conical face oppositely disposed to the conical faceo'f said third flange, rotationally fixedwith respect to said other shaft but axially slidable the n, and adapted to be urged awa from said third flange by an external means; at least one pair of conical faced fixedly interspaced flanges having the-conical s'i1r' faces thereof oppositely disposed, free to slide axially on said other shaft; said third fixedflange being the second flange from one end of said group of pulleys on [said other shaft and said fourth thrust flange being the !second flange from the other end of said group of pulleys vton said other shaft; and a V belt disposed between each oppositely disposed pair of conical pulley flanges on said one shaft and between an oppositely disposed pair of conical pulley flanges on said other shaft, urging said lflanges apart and spacing said flanges to provide equal tension in said belts and continuously parallel belt alignment at all speed ratios of said power transmission apparatus.

7. In a multibelt power transmission apparatus, including a driving shaft and a pair of driven shafts; a plurality of pulleys on said driving shaft comprising: at least two flared flanges fixed to said driving shaft, at least two pairs of oppositely disposed, fixedly interspaced flared flanges, free to slide axially on said driving-shaft, and another pair of oppositely disposed flared thrust flanges axially slidable as an interconnected unit on said driving shaft; and a group of pulleys oneachof said driven shafts, each group comprising: a flared flange fixed to its driven shaft, at least one pair of oppositely disposed fixedly interspaced flared flanges, free to slide axially on its driven shaft, a flared thrust flange axially slidable a interspaced flanges cooperating, respectively, with the fixed flanges and the thrust flanges on their respective shafts to define pulleys, and a V-belt connecting each driving shaft pulley with a driven shaft pulley.

8. In a multibelt power transmission apparatus, including a driving shaft and a pair of driven shafts; a plurality of pulleys on said driving shaft comprising: at least two oppositely disposed flared flanges fixed to said driving shaft, positioned at each end of the group of flanges constituting said pulleys, at least two pairs of oppositely disposed, fixedly interspaced flared flanges free to slide axially on said driving shaft and having one flange of each pair opposite one of said fixed flanges, and another pair of oppositely disposed flared thrust flanges axially slidable as an interconnected unit on said driving shaft; one flange of said another pair being urged toward one of said fixed flanges by external means and the other of said another pair being urged toward the other of said fixed flanges by external means,'said first and second external means acting equally; and a group of pulleys on each of said driven shafts, each such group comprising: a flared flange fixed to its driven shaft, at least one pair of oppositely disposed, fixedly interspaced flared flanges free to slide axially on its driven shaft, and a flared thrust flange axially slidable relative to its driven shaft and adapted to be urged away from said fixed flange on said driven shaft by external means, one flange of said at least one pair of fixedly interspaced flanges on each driven shaft being a flange of a pulley with said fixed flange on that driven shaft; and a plurality of belts disposed between opposite.

pulleys on said driving and driven shafts.

rality of pulleys combined on each of said shaft means,

and an edge-active belt connecting each pulley on said 1 driving shaft means with a pulley on said driven shaft means, said pulleys on one of said shaft means comprising a flared flange fixed with respect to said one shaft means, with the active surface thereoffaced outward of" the center of said combined pulleys; a flared thrust flange oppositely disposed to said fixed flange, rotationally fixed with respect to said one shaft-means but axially slidable References Cited in the file of this patent 1 r UNITED. STATES PATENTS relative thereto, with the active surface thereoflfaced Reeves; outward 0f the center of said combinedpulleys, and m-ged 5 7 ,299,921 Myers Oct. 27, away from said fixed flange by an external force-producing 2,342,941 I 011M011 means and urged toward said fixedflange by said edge 2,420,100 Salsbury May 6, active belt; and at least one pair of fixedly interspaced 2,503,462 I Wyzenbeek Apr. 11, oppositely disposed flared flanges free to slide axially on a "i i said one shaft means, one flange of saidiat least one pair 10 FOREIGN PATENTS coaeting with said fixed flange to define a pulley.

Great Britain Oct. 11, 1949 

